Color sensors are utilized in printing systems to detect color reproduction accuracy. In operation, light reflected from a sample formed on a print medium is captured by a sensor array. The output from the array is analyzed to identify the color of the sample. System parameters may be adjusted when the identified color differs from that which is expected. While samples of identical color may be formed on two different print media, certain events can cause color sensor to identify the two samples as being of different colors causing the printing system to make unnecessary and perhaps undesirable corrections. For example, the samples may be formed on print media of different thicknesses such that the second sample is positioned closer to the sensor array. The differing positions, absent correction, may cause the two samples to be identified being of different colors. In another example, the samples may be formed on two different types of print media having differing scattering profiles. For example, one sample may be formed on glossy paper while the second is formed on paper having a matte finish. The differing scattering profiles, absent correction, may cause the two samples to be identified being of different colors.